From c3955b4db6dcb1b2c815cfe684e57caaa12b6b6c Mon Sep 17 00:00:00 2001
From: Alberto Griggio <griggio@fbk.eu>
Date: Mon, 5 Dec 2005 16:48:44 +0000
Subject: [PATCH] added function term_of_equality to re-build the Cic.term from
 an equality

---
 helm/ocaml/paramodulation/inference.ml  | 26 +++++++++++++++++++++++++
 helm/ocaml/paramodulation/inference.mli |  5 +++++
 2 files changed, 31 insertions(+)

diff --git a/helm/ocaml/paramodulation/inference.ml b/helm/ocaml/paramodulation/inference.ml
index 105b708e9..5633599d2 100644
--- a/helm/ocaml/paramodulation/inference.ml
+++ b/helm/ocaml/paramodulation/inference.ml
@@ -922,3 +922,29 @@ let is_identity ((metasenv, context, ugraph) as env) = function
           (fst (CicReduction.are_convertible 
 		  ~metasenv:(metasenv @ menv) context left right ugraph)))
 ;;
+
+
+let term_of_equality equality =
+  let _, _, (ty, left, right, _), menv, args = equality in
+  let eq i = function Cic.Meta (j, _) -> i = j | _ -> false in
+  let argsno = List.length args in
+  let t =
+    CicSubstitution.lift argsno
+      (Cic.Appl [Cic.MutInd (LibraryObjects.eq_URI (), 0, []); ty; left; right])
+  in
+  snd (
+    List.fold_right
+      (fun a (n, t) ->
+         match a with
+         | Cic.Meta (i, _) ->
+             let name = Cic.Name ("X" ^ (string_of_int n)) in
+             let _, _, ty = CicUtil.lookup_meta i menv in
+             let t = 
+               ProofEngineReduction.replace
+                 ~equality:eq ~what:[i]
+                 ~with_what:[Cic.Rel (argsno - (n - 1))] ~where:t
+             in
+             (n-1, Cic.Prod (name, ty, t))
+         | _ -> assert false)
+      args (argsno, t))
+;;
diff --git a/helm/ocaml/paramodulation/inference.mli b/helm/ocaml/paramodulation/inference.mli
index 55f3df414..30927dc72 100644
--- a/helm/ocaml/paramodulation/inference.mli
+++ b/helm/ocaml/paramodulation/inference.mli
@@ -109,6 +109,11 @@ exception TermIsNotAnEquality;;
 *)
 val equality_of_term: Cic.term -> Cic.term -> equality
 
+(**
+   Re-builds the term corresponding to this equality
+*)
+val term_of_equality: equality -> Cic.term
+
 val term_is_equality: Cic.term -> bool
 
 (** tests a sort of alpha-convertibility between the two terms, but on the
-- 
2.39.2